The present invention relates to a transmitter of a tire condition monitoring apparatus that permits a driver in a vehicle passenger compartment to check the conditions of tires, such as the air pressure, and to a tire condition monitoring apparatus.
Wireless tire condition monitoring apparatuses that allow a driver in a vehicle passenger compartment to check the conditions of vehicle tires have been proposed. One such monitoring system includes transmitters and a receiver. Each transmitter is located in one of the wheels and the receiver is located in the body frame of the vehicle. Each transmitter detects the conditions, such as air pressure and the temperature of the associated tire, and wirelessly transmits the detected information at predetermined intervals. The receiver receives data from the transmitters and displays the conditions of the tires, for example, on a display located in front of the driver's seat.
To extend the life of batteries, apparatuses that do not carry out data transmission when the vehicle is not moving have been provided. In such an apparatus, data transmission is resumed immediately after movement of the vehicle is detected.
Specifically, all the transmitters start transmitting data at the same time after movement of the vehicle is detected. Therefore, radio waves from the transmitters interfere with one another. This hinders the receiver from correctly receiving data from the transmitters. Particularly, in a vehicle having a great number of tires, such as trucks and buses, reception of data is more difficult.